A new technique to degrade bituminous coals and lignites using alkali in liquid paraffin at the plastic state of coals has been developed. More than 60% of coal can be rendered extractable. The technique is very simple and does not involve the use of pressure. The technique could be of interest for structural studies on coal. The technique is also utilized for obtaining ash-free, high calorific value (a clean fuel) from coals and lignites.